Claustropyga triloba, Vilkamaa, Pekka & Hippa, Heikki, 2007

Vilkamaa, Pekka & Hippa, Heikki, 2007, Review of the Nearctic Claustropyga Hippa, Vilkamaa & Mohrig (Diptera, Sciaridae) with the description of three new species, Zootaxa 1552, pp. 53-68 : 65-67

Claustropyga triloba sp. n.

Fig. 7 A–E

Material studied. Holotype male. CANADA, Yukon Territory, Ogilvie Mts., North Fork Pass, 4100’, 21.VI.1962, P. J. Skitsko ( CNC). Paratypes. Same data as holotype, 3 males ( CNC), North Fork Crossing, Mi. 43, Peel Plt Rd., 3500’, 3.VII.1962, P.J. Skitsko, 2 males ( CNC), same data but 4.VII., 1 male ( CNC) and same data but 5.VII., 1 male ( CNC).

Male. Head almost unicolorous pale brown. Eye bridge 2–3 facets wide. Face (prefrons) with 10–17 setae. Clypeus non-setose or with 1 seta. Antennal flagellomeres 4 and 5, Fig. 7 B. Maxillary palpus, Fig. 7 A, with three palpomeres. Palpomere 1 with 1–4 setae, palpomere 2 with 2–8 setae, palpomere 3 with 3–6 setae. Thorax pale brown, indistinctly paler on the middle part of pleura, and laterally and at the row of dorsocentral setae on scutum. Scutum and scutellum as in C. brevichaeta ( Hippa et al. 2003, Fig. 3 a) but the number of lateral setae on scutum ca. 25 of which ca. 6 very strong, stronger than the strongest dorsocentral setae; the number of scutellar setae ca. 20. Anterior pronotum with 3–5 setae. Posterior pronotum with 0–2 setae. Other pleural sclerites non-setose. Episternum 1 with 5–8 setae. Wing, Similar to Fig. 4 C: pale yellowish-brown. Wing length 20– 2.5 mm, width/length 0.4. c/ w 0.8. R1/R 0.7–1.1. Haltere pale yellowish-brown. Legs pale yellowish-brown. Apex of fore tibia, Fig. 7 C. Length of fore basitarsomere/length of fore tibia 0.5–0.6. Length of hind tibia/length of scutum and scutellum 1.8–2.2. Abdomen pale brown, concolorous with thorax. Sternite 8 with 9–17 setae. Hypopygium, Fig. 7 D, E. Intercoxal lobe semicircular, with a medial gap in the setosity. Gonostylus with two mid-mesial megasetae, one at the ventral margin, the other more dorsal and arising from a large basal body, and two large apical mesial megasetae ventrally from an apical tooth. Tegmen rather weakly sclerotized, with large lateral lobes (shoulders) and a broad apical lobe, all nearly equal in size. Hypoproct (sternite 10) non-setose or with one seta on each side.

Female unknown.

Discussion. Claustropyga triloba is not very similar to any other described Claustropyga . The hypopygium bears a rather superficial similarity to C. subcorticis , especially in having only two mid-mesial megasetae. C. triloba differs by having these megasetae larger and by having one of them arising from a large basal body, which is as long as the megaseta, whilst in C. subcorticis the mesial megasetae lack a basal body, which is distinctly more than only the socket. Furthermore, the ventral surface of the gonostylus is evenly convex whereas in C. subcorticis there is an abruptly flattened apical part; and in C. triloba the ventral setae of the gonostylus are normal, whereas in C. subcorticis there are unusually strong and long setae posteriorly on the convex ventral part. C. triloba has a unique tegmen with three subequal lobes. The gonostylus of C. triloba has a superficial resemblance to some species of Camptochaeta Hippa & Vilkamaa , e.g. C. bournei (Shaw) (see Hippa and Vilkamaa 1994), but is at once distinguished by the presence of a large intercoxal lobe on the hypopygium; by the lack of a flagellate seta mesially on the gonostylus; by a non-bordered patch of setae apically on fore tibia; and by the absence of a sensory pit on the basal palpomere.

Figures

FIGURE 3. Part of hypopygium (A, C) and gonostylus (B, D) in ventral view. A and B: Claustropyga auriculata Hippa, Vilkamaa & Mohrig (from Alaska). C and D: C. subcortici s Mohrig & Krivosheina (from Alaska). Scale 0.10 mm.

FIGURE 4. Claustropyga mirifica sp. n. (holotype): Antennal flagellomere 4 in ventral view (A), maxillary palpus in dorsal view (B), wing in dorsal view (C), part of hypopygium (D) and gonostylus (E) in ventral view. Scale 0.10 mm, in C 1.0 mm.

FIGURE 7. Claustropyga triloba sp. n. (holotype). Maxillary palpus in dorsal view (A), antennal flagellomeres 4 and 5 in ventral view (B), apical part of fore tibia in prolateral view (C), and part of hypopygium (D) and gonostylus (E) in ventral view. Scale 0.10 mm.